Featured Research

from universities, journals, and other organizations

Surf's Up: Historic Glenn Mission And Soho Make Major Advance On 37-Year-Old Solar Mystery

Date:
July 9, 1999
Source:
National Aeronautics And Space Administration
Summary:
The high-speed portion of the solar wind achieves its unexpectedly high velocity -- up to 500 miles per second -- by "surfing" magnetic waves in the Sun's outer atmosphere, according to observations made by two spacecraft during John Glenn's return to space.

The high-speed portion of the solar wind achieves its unexpectedly high velocity -- up to 500 miles per second -- by "surfing" magnetic waves in the Sun's outer atmosphere, according to observations made by two spacecraft during John Glenn's return to space.

For 37 years, solar scientists have been puzzled by the fact that the high-speed solar wind travels twice as fast as predicted by theory. Observations and theoretical analyses have discovered a surprising explanation for this mystery: magnetic waves. The observations were made using instruments aboard NASA's Spartan 201 spacecraft, deployed from the Space Shuttle during the STS-95 mission, and the international Solar and Heliospheric Observatory (SOHO).

"The mystery was first presented by the Mariner 2 spacecraft in 1962, the same year as Glenn's first flight," said Dr. Marcia Neugebauer of NASA's Jet Propulsion Laboratory, Pasadena, CA, the co-principal investigator of the solar wind instrument on Mariner 2. "The new observations made by SOHO and by the Spartan 201 mission during Glenn's return to space put us much closer to finally unraveling the mystery of the acceleration of the solar wind."

The outermost solar atmosphere, or corona, is an extremely tenuous, electrically charged gas that is seen from Earth only during a total eclipse of the Sun by the moon, when it appears as a shimmering white veil surrounding the black lunar disk. Using Spartan and SOHO, scientists have detected rapidly vibrating magnetic fields within the corona that form magnetic waves that appear to accelerate the solar wind.

"These vibrating magnetic waves give solar wind particles a push, just like an ocean wave gives a surfer a ride," said Dr. John Kohl, a senior astrophysicist at the Smithsonian Astrophysical Observatory in Cambridge, MA, and the principal investigator for ultraviolet spectrometers aboard SOHO and the Spartan 201.

The electrical charges of solar wind particles, or ions, force them to spiral around invisible magnetic lines in the corona as they rush into space. When the lines vibrate, as they do in a magnetic wave, the spiraling ions are accelerated out and away from the Sun. The presence of magnetic waves in the corona was inferred by observing the motions of these solar wind ions. "We were quite surprised to find that heavier oxygen ions actually moved faster than lighter hydrogen ions," said Dr. Steven Cranmer of the Harvard-Smithsonian Center for Astrophysics in Cambridge, MA. "The best explanation for this is a magnetic field line that wiggles back and forth in the same amount of time that oxygen ions take to spiral around it. Just as a child riding on a swing moves higher if someone pushes with the right rhythm, the resonant magnetic waves give a boost to the oxygen ions." The scientists believe there are magnetic waves in the corona with many different "wiggling periods," or frequencies. These waves accelerate various solar wind particles that spiral around the field lines at different rates. The observations also will help scientists better understand solar regions called coronal holes. "Solar winds from these regions enhance energetic electrons in the Earth's Van Allen radiation belts, which can sometimes affect the electrical systems aboard Earth-orbiting satellites," said Joseph W. Hirman, Chief of the Division for Space Weather Operations at the Space Environment Center operated by the National Oceanic and Atmospheric Administration in Boulder, CO. Even with this major discovery, there are questions left to answer. "The observations have made it abundantly clear that heavy particles like oxygen 'surf' on the waves, and there is also mounting evidence that waves are responsible for accelerating the hydrogen ions, the most common constituent of the solar wind," Cranmer said. "Other common particles, such as helium, have never been observed in the accelerating part of the corona, and new observations also are needed to refine our understanding of how the waves interact with the solar wind as a whole."

The SOHO mission is sponsored by NASA and the European Space Agency. This research was published in the June 20 edition of the Astrophysical Journal.


Story Source:

The above story is based on materials provided by National Aeronautics And Space Administration. Note: Materials may be edited for content and length.


Cite This Page:

National Aeronautics And Space Administration. "Surf's Up: Historic Glenn Mission And Soho Make Major Advance On 37-Year-Old Solar Mystery." ScienceDaily. ScienceDaily, 9 July 1999. <www.sciencedaily.com/releases/1999/07/990709083541.htm>.
National Aeronautics And Space Administration. (1999, July 9). Surf's Up: Historic Glenn Mission And Soho Make Major Advance On 37-Year-Old Solar Mystery. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/1999/07/990709083541.htm
National Aeronautics And Space Administration. "Surf's Up: Historic Glenn Mission And Soho Make Major Advance On 37-Year-Old Solar Mystery." ScienceDaily. www.sciencedaily.com/releases/1999/07/990709083541.htm (accessed July 31, 2014).

Share This




More Space & Time News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Supply Ship Takes Off for International Space Station

Supply Ship Takes Off for International Space Station

AFP (July 30, 2014) The European Space Agency's fifth Automated Transfer Vehicle (ATV-5) is takes off to the International Space Station on an Ariane 5 rocket from French Guiana. Duration: 00:34 Video provided by AFP
Powered by NewsLook.com
Raw: Rocket Launches Into Space With Cargo Ship

Raw: Rocket Launches Into Space With Cargo Ship

AP (July 30, 2014) Arianespace launched a rocket Tuesday from French Guiana carrying a robotic cargo ship to deliver provisions to the International Space Station. (July 30) Video provided by AP
Powered by NewsLook.com
In Virginia, the Rise of a New Space Coast

In Virginia, the Rise of a New Space Coast

AP (July 30, 2014) Every summer, tourists make the pilgrimage to Chincoteague Island, Va. to see wild ponies cross the Assateague Channel. But, it's the rockets sending to supplies to the International Space Station that are making this a year-round destination. (July 30) Video provided by AP
Powered by NewsLook.com
Russia Saves Gecko Sex Satellite, Media Has Some Fun With It

Russia Saves Gecko Sex Satellite, Media Has Some Fun With It

Newsy (July 27, 2014) The satellite is back under ground control after a tense few days, but with a gecko sex experiment on board, the media just couldn't help themselves. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

    Technology News



      Save/Print:
      Share:

      Free Subscriptions


      Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

      Get Social & Mobile


      Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

      Have Feedback?


      Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
      Mobile: iPhone Android Web
      Follow: Facebook Twitter Google+
      Subscribe: RSS Feeds Email Newsletters
      Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins